Denis Beaudoin, who says he may be the biological father of the older children of Nadya Suleman, the California woman who recently gave birth to octuplets, has stepped forward to shed further light on the single mom of 14.

In an interview Monday on ABC's Good Morning America, Beaudoin – who claims he dated Suleman for about three years in the '90s – says he agreed to donate sperm for her during a visit to a clinic where she was to receive in-vitro fertilization. "I kind of thought it was unusual," he said of Suleman's request, but "she really wanted to have kids." He also said he "cared for her."

Beaudoin recalled Suleman as "fun" and "a really great girl [with] an infectious laugh." Friends had nicknamed her "Giggles."

Suleman has denied Beaudoin is the father of her children, claiming he was infertile. Suleman's representative, Victor Munoz, tells PEOPLE, "The real sperm donor knows who he is. This guy is definitely not the one. It's kind of comical. Nadya's not sure why he's doing this." Today, Beaudoin is married and the father of two children.

Claimed She Had Ovarian Cancer

Beaudoin said he was "shocked [and] surprised" when he first learned that Suleman, whom he claims he dated from 1997 to 1999, had delivered octuplets on Jan. 23. On top of all else, Beaudoin told GMA, Suleman had informed him that the doctors told her "she had ovarian cancer," he said.

Beaudoin – who is bi-racial – says Suleman's older children resemble him – and is pushing for a paternity test. He says he is willing to help Suleman raise all her children because he doesn't believe she can do so on her own. "Either which way, you know, know that if she needs it, I'll lend a helping hand," he says.